Method for culturing microorganisms on a growth substrate comprising biomass obtained from methanotrophic bacteria

Abstract

The invention relates to a microorganism growth substrate which comprises a sterile nutrient composition derived from the biomass of a culture of bacteria including methanotrophic bacteria and further containing at least one sterile nutrient. A preferred biomass material is that derived from a microbial culture comprising Methylococcus capsulates (Bath) (strain NCIMB 41526), Ralstonia sp. DB3 (strain NCIMB 41527) and Brevibacillus agri DB5 (strain NCIMB 41525), optionally in combination with Aneurinibacillus sp. DB4 (strain NCIMB 41528).

The invention claimed is: 
     
       1. A method of culturing a microorganism which comprises culturing a microorganism in a broad spectrum growth medium that is a sterile nutrient composition comprising the biomass of a culture comprising methanotrophic bacteria,
 wherein the culture comprising methanotrophic bacteria used to produce the biomass comprises at least 50% by weight methanotrophic bacteria relative to the total bacterial weight of the biomass, 
 wherein the biomass comprises  Methylococcus capsulatus  (Bath), NCIMB 41526,  Ralstonia  sp. DB3, NCIMB 41527 , Brevibacillus agri  DB5, NCIMB 41525, and  Aneurinibacillus  sp. DB4, strain NCIMB 41528, 
 wherein the growth medium comprises a hydrolysate, homogenate or autolysate of the biomass of methanotrophic bacteria, and at least one nutrient selected from the group consisting of: (a) glucose; and (b) nitrate and mineral salts. 
 
     
     
       2. The method as claimed in  claim 1 , wherein said nutrient composition comprises a hydrolysate, homogenate or autolysate of said biomass. 
     
     
       3. The method as claimed in  claim 1 , wherein said growth medium further comprises at least one nutrient selected from the group consisting of: (a) glucose; and (b) nitrate and mineral salts. 
     
     
       4. The method as claimed in  claim 1 , wherein the glucose is present in said growth medium in a dry mass basis weight ratio of 5:1 to 1:5, relative to the sterile nutrient composition. 
     
     
       5. The method as claimed in  claim 1 , wherein the nitrate and mineral salts are present in said growth medium in a weight ratio of 0.01″1 to 0.2:1, relative to the sterile nutrient composition. 
     
     
       6. The method as claimed in  claim 1 , wherein said culture of bacteria is produced by fermentation on hydrocarbon fractions or on natural gas. 
     
     
       7. The method as claimed in  claim 1 , wherein said nutrient composition comprises an autolysate of said biomass. 
     
     
       8. The method as claimed in  claim 1 , wherein said mineral salts are selected from the group consisting of potassium, calcium, magnesium, sodium, molybdenum, iron, zinc, boron, cobalt, manganese and nickel compounds. 
     
     
       9. The method as claimed in  claim 4 , wherein the glucose is present in said growth medium in a dry mass basis weight ratio of 2:1 to 1:2, relative to the sterile nutrient composition. 
     
     
       10. The method as claimed in  claim 5 , wherein the nitrate and mineral salts are present in said growth medium in a weight ratio of 0.05:1 to 0.1:1, relative to the sterile nutrient composition. 
     
     
       11. The method as claimed in  claim 1 , wherein the culture of bacteria used to produce the biomass is at least 60% by weight methanotrophic bacteria relative to the total bacterial weight. 
     
     
       12. The method as claimed in  claim 11 , wherein the culture of bacteria used to produce the biomass is at least 70% by weight methanotrophic bacteria relative to the total bacterial weight. 
     
     
       13. The method as claimed in  claim 12 , wherein the culture of bacteria used to produce the biomass is at least 75% by weight methanotrophic bacteria relative to the total bacterial weight. 
     
     
       14. The method as claimed in  claim 13 , wherein the culture of bacteria used to produce the biomass is 75% to 95% by weight methanotrophic bacteria relative to the total bacterial weight. 
     
     
       15. The method as claimed in  claim 14 , wherein the culture of bacteria used to produce the biomass is 75 to 80% by weight methanotrophic bacteria relative to the total bacterial weight. 
     
     
       16. The method as claimed in  claim 6 , wherein said culture of bacteria is produced by fermentation on natural gas.